Dongxu Gu

Bio: Dongxu Gu is an academic researcher from University of Electronic Science and Technology of China. The author has contributed to research in topics: Copolymer & Ethylene glycol. The author has an hindex of 1, co-authored 3 publications receiving 1 citations.

Design of gel-to-sol UCST transition peptides by controlling polypeptide β-sheet nanostructures

Abstract: Creating stimulus-responsive materials solely by controlling polypeptide secondary nanostructures is challenging. We synthesized a methyl poly(ethylene glycol)-b-poly(O-benzyl-L-threonine) (mPEG-PBnLT) diblock copolymer that exhibited gel-to-sol UCST (Upper Critical Solution Temperature) transition behavior in an aqueous solution. The transition temperature window was easily adjusted by changing the copolymer concentration or length of the PBnLT block. Disassembly of the initial β-sheet nanoassemblies caused nanofibril transformation to spherical aggregates with increasing temperature, resulting in a gel-to-sol UCST transition. This result inspires a brand-new strategy for the structural design and functional control of materials. A novel thermoresponsive diblock copolymer of methyl poly (ethylene glycol)-b-poly (O-benzyl-L-threonine) was synthesized. The copolymer solutions exhibited gel-to-sol UCST transition behavior with temperature. The gel-to-sol transition was due to the disassembly of the initial β-sheet layered nanoassemblies that induced the transformation of self-organized morphology from nanosized fibrils to spherical aggregates.

Constructing BiOBr/g-C3N4/Bi2O2CO3 Z-scheme photocatalyst with enhanced photocatalytic activity

Abstract: In this work, the novel camellia-structured double Z-scheme BiOBr/g-C3N4/Bi2O2CO3 was simply prepared by a hydrothermal method. XRD, FTIR, SEM, TEM, XPS, UV-DRS, and PL were used to investigate the composition, morphology, chemical condition, and optical properties of the prepared samples, respectively. The ternary heterojunction photodegraded Rhodamine B under visible light within 60 min with much higher degradation efficiency (98 %) comparing with pure BiOBr, g-C3N4, and Bi2O2CO3. Radical trapping experiments and ESR results exhibited the main reactive species (·O2− and ·OH) during the degradation process. The formation of dual Z-scheme heterojunction improved the rate of charge separation, enhanced the absorption of visible light, and thus promoted the photocatalytic activity. The BiOBr/g-C3N4/Bi2O2CO3 photocatalysts are a promising material for the removal of dye in effluents.

Research progress of self-assembling peptide hydrogels in repairing cartilage defects

Abstract: Due to the lack of blood vessels, nerves and lymphatic vessels, the capacity of articular cartilage to heal is extremely limited. Once damaged, it is urgent for articular cartilage to repair the injury. In recent years, there has been an increase in cartilage tissue engineering studies. Self-assembling peptide hydrogel as a kind of hydrogels composed of peptides and water is widely used in cartilage tissue engineering. Under noncovalent interactions such as electrostatic interaction, hydrophobic interaction, hydrogen bonding and pi-pi stacking force, peptides self-assemble into three-dimensional (3D) structures that mimic the natural extracellular matrix and allow cells to grow, proliferate and differentiate. Because SAPHs have excellent biocompatibility and biodegradability, variable mechanical properties, low immunogenicity, injectability, and the ability to load cells and bioactive substances, many researchers utilized them to promote the repair and regeneration of articular cartilage after damage. Therefore, the purpose of this review is to sum up the composition, injury characteristics, and treatments of articular cartilage, as well as the action of SAPHs in repairing articular cartilage damage.